This command is used to do low level copying of data.

learn more… | top users | synonyms

4
votes
4answers
462 views

IDE compatability with SATA image

We had an old CNC machine's hard-drive fail recently. The hard-drive is an old 1275MB IDE (Seagate) and there were defiantly bad sectors on it. I was able to image the contents of the drive onto a ...
1
vote
2answers
827 views

Large delay starting “dd” write in background in bash even when using nohup

I wrote a small script to print the memory usage during a large sequential write of a file. #!/bin/bash rm result echo 3 > /proc/sys/vm/drop_caches sync; echo start nohup time dd if=/dev/zero of=...
1
vote
2answers
115 views

Cloning a two partition HDD onto a smaller HDD and maintaining MBR

I have a hard disk(A) containing two partitions - A1 is a NTFS partition containing a windows OS, and A2 is an NTFS partition containing data. I want to copy both of these partitions onto a different, ...
0
votes
2answers
136 views

how to boot from a backup disk created by dd

I use dd command to backup a disk. # dd if=/dev/sda of=/dev/sdb but when I boot from the backup disk, I got a error message check filesystem failed! I do not know how to settle this problem. I ...
0
votes
2answers
592 views

ddrescue a non-solaris disk gets I/O error

I am trying to get a disk image of a SCSI disk using ddrescue on Solaris10 (Sparc). The disk is non-solaris, and ddrescue gets an immediate I/O error (as does dd). I used format to label the disk as ...
2
votes
1answer
37 views

how to intentionally damage linux MBR (RHEL 7) on disk for test purpose?

I am running tests for MBR recovery on Red Hat Linux 7. I tried to intentionally erase the MBR with: dd if=/dev/random of=/dev/sda bs=1 count=512 I can see with fdisk -l /dev/sda that the ...
1
vote
1answer
61 views

Installing CentOS on HP Server, SSDs connected to a RAID controller

I am trying to install centOS 6.0 in this HP Server, I contacted with the support and they said me that it supports that OS. I have no problem installing it on a SSD that is connected directly to ...
1
vote
1answer
513 views

On a system with 64GB mem the Linux Buffer run full while copying with dd to dev null and io stops till manual drop_caches

I am running a server with linux software raid 10. It is a dual CPU system with 64GB Ram. 2x16GB dimms related to each of the CPUs. I want to use dd to backup kvm virtual machines and run into a ...
0
votes
1answer
37 views

How to use dd to dump an image to unallocated space

I have a bin file (chromiumos_image.bin) which contains some (around 12) partitions, which I need to dump into the unallocated space between 2 other partitions. The partition table is this: My ...
0
votes
1answer
316 views

fio on virtual disk created with dd to stress disk

I am trying to create a script for my coworkers to use in the field that will stress the internal disks to a Linux server. I plan to put some logic in for finding the /dev/sd's available and such. But ...
0
votes
1answer
131 views

When copying VM filesystem over netcat, dd copies double the disk size

I'm attempting to copy the disk of a working headless virtualbox VM (VM1) on one server to a new VM (VM2) on a vCloud server. I don't have access to the host of VM2. The OS is Windows Server 2003 (32-...
0
votes
1answer
130 views

dd or cat - overload when read /dev/zero

I need reclamation thin disk, so Im trying fill zero on vhdd. But when I run it, so server is overload with 20k IOPS and full satured SAN network. Can you help me how I can slow b/w for this? E.g 10MB/...
0
votes
1answer
79 views

handle multiple calls of rsync, dd and snapshot

The server runs the following operations often. It takes a snapshot of a logical volume, then backup up the content to the remote backup server. It is possible that multiple backups and transfer ...
0
votes
1answer
379 views

1. XFS: how to find path / directory of inodes 2. XFS in a file -o loop and ddrescue?

how to find the full original file/directory path of some damaged XFS inodes? and how to list the last modified few 10000 inodes (=edited or moved files/directories) rapidly among millions of ...
3
votes
0answers
2k views

Cloning a bitlocker encrypted disk

Our company's had its laptops for just over 2 years now and they have all become slow and many of them have had their harddisks dying randomly lately. I noticed that many of my colleagues use a tilted ...
1
vote
0answers
415 views

Slow IO Performance with PERC H700/710 with current linux distributions

we noticed really bad write performance, on our new Dell R720 with Perc 710. Especially when it come to writing a lot of small files. The funny thing is that this bad performance only occurs on newer ...
1
vote
0answers
189 views

How to restore a dd image to an EBS volume

I have a local dd image myimage.bin, which I want to use to create an AWS EBS volume. The only way I can figure out how to do this is to, 1) Launch an AWS instance 2) Create and attach an EBS ...
1
vote
0answers
1k views

Differences between hdparm --read-sector and dd with “Current Pending Sectors”

This was originally an "answer" to How to use hdparm to fix a pending sector? I'd been getting SMART notifications for the same "Current Pending Sector" for days. The dd solutions around weren't ...
1
vote
0answers
322 views

Backing up VMs to a tape drive

I've got myself one of these fancy tape drives, HP LTO2 with 200/400 GB cartridges. The st driver reports it like this: scsi 1:0:0:0: Sequential-Access HP Ultrium 2-SCSI T65D I can ...
1
vote
0answers
654 views

Heavy disk write on a Debian VPS gives “ata1: lost interrupt (Status 0x50)”

I have a new Debian VPS that appears to fail almost every time I run a heavy disk write test on ext4 filesystem. The filesystem goes to read-only mode and "ata1: lost interrupt (Status 0x50)" is ...
0
votes
0answers
12 views

DD + LVM Snapshot + Space shortage

Here is the scenario : I have a production system that can't be shutdown for very long, it has the following root filesystem LVM: [root@an2 ~]# df -h Filesystem Size Used ...
0
votes
0answers
36 views

ZFS mirror migrated to other system with dd -> zpool import fails

I'm pretty new to ZFS and this might be an easy problem (but I don't find any discussions about how to do this): I've messed up a FreeBSD installation on a Root-on-ZFS mirrored ZFS Pool on a ...
0
votes
0answers
26 views

Shrinking an img file that contains linux partitions

I've got an img file (4,02GB) containing a Linux OS. My goal is to shrink this img filed down to < 4GB. The img contains a linux partition that only holds about 2,5GB of data. I need to be able to ...
0
votes
0answers
313 views

Creating IPsec tunnel Ubuntu 15.04 ip sec tools

I'm trying to setup a VPN/Tunnel between three(3) Ubuntu 15.04 servers. I've googled and it seems that I can use IPsec tools for this. I've only found the following tutorial:https://help.ubuntu.com/...
0
votes
0answers
1k views

Create a VHD file from a Linux disk

I have a disk containing CentOS 5.8 that was removed from a dead box. I would like to make a VHD file from this disk so I can run a virtual machine (instead of a new physical machine). The Virtual ...